1. Field of the Invention
The present invention relates to a light emitting diode (LED). More particularly, the present invention relates to a light emitting diode with shortened conducting wires to improve component's reliability.
2. Description of Related Art
With progress in chip manufacturing, the operating power of light emitting diodes has been improved to comply with light source standards. Following light source standards have become increasingly important in the heat dissipating designs of light emitting diodes.
When the chips are lit, the light emitting diodes generate heat. This heat must be dissipated. Currently the heat is dissipated from the interior of the light emitting diode through a metallic heat sink connected to the bottom of the chip. In order to enhance heat dissipating efficiency, the metallic heat sink is typically bulky, which results in increasing the volume of the entire light emitting diode device structure, and elongates wires for electrical connection between the chip and the leads or substrate.
When the light emitting diode is operated in environments with extreme temperature variations, the wires are easily pulled by the differentiation of the coefficient of thermal expansion between different packaging materials or components, and eventually break causing product reliability problems of the light emitting diode.
Refer to FIG. 1. A conventional design of a light emitting diode 100 is illustrated. The light emitting diode 100 comprises a heat sink 110, a chip 120, a first wire 131, a second wire 132, a first lead 141, a second lead 142, an insulating housing 150, a packaging member 160 and a lens 170. The insulating housing 150 may be insulating plastic.
The chip 120 is an LED chip and is mounted on the heat sink 110. The wires 131 and 132 respectively connect the chip 120 with the leads 141 and 142 so as to establish the electrical connection to provide electricity to the chip 120. The insulating housing 150 holds the heat sink 110 and the leads 141 and 142 in position. The packing member 160 may use resin and is injected to cover the chip 120 and the wires 131, 132 around the inside of the insulating housing 150. The lens 170 encapsulates the packing member 160 with the insulating housing 150 and the heat sink 110 to form the light emitting diode 100.
When the heat sink 110 is bulky or its size is increased, the lengthy wires 131 and 132 may be pulled and dragged to break because of differentiation of the coefficient of thermal expansion among the package member 160, the wires 131 and 132, the heat sink 110 etc. in environments with extreme temperature variations. Thus, the product's reliability is lowered.
Therefore, there is a need to provide an improved light emitting diode device having simplified structure and high heat dissipating efficiency without changing substantially current production process to mitigate or obviate the aforementioned problems.